What type of low-tech weapons are supporters of Egypt's President Hosni Mubarak using to attack the protestors in Cairo? Think rocks, camels, Molotov cocktails, space heaters and even a cavalry charge.

Egypt runs an ultra-modern security state, with extensive experience wielding the latest tools of repression. That was on display when the government shut down the Internet for six days in order to break up massive protests against President Hosni Mubarak. But as Mubarak's thugs go into suppression mode against protesters in Cairo, they're using low-tech weapons to injure an estimated 500 people at Tahrir Square.

The intensifying crackdown is decidedly old school. There was a cavalry charge into Tahrir Square: as the Army hung back in its armored personnel carriers, plainclothes police forces - some of their ID cards, captured by protesters, were shown on TV - rode camels and horses, attempting to break demonstrator phalanxes with wooden sticks.

The equine assault was a stark contrast to the Egyptian Army's armored personnel carriers in the square. After calling on the demonstrators to go home earlier Wednesday, the Army has stayed out of the assault, although some of its carriers became roadblocks to separate the warring factions. Journo/blogger Issandr El Amrani explains that presence of the horses and camels indicates that the regime "recruited from the stables near the Pyramids" to make up its hit squad.

There was some sporadic gunfire - apparently warning shots from the Army - but the signature projectile of the day is a rock. Al Jazeera reported that the pro-regime forces were using "sticks with nails," knives, "homemade swords," chairs, and bits of masonry to attack the demonstrators. Its reporter Dan Nolan watched "guys in front of me poundin on pavement to break it into sizes they can throw."

Aluminum siding became makeshift shields and checkpoints. On the terraces above the square, presumed pro-Mubarak forces rained metal appliances - I thought I saw a space heater thrown - down onto the crowds.

One journalist spotted people throwing "fire bombs at protesters." Molotov cocktails are being thrown with "increased frequency" as night has fallen, Al Jazeera reports. That's as high-tech as the violence has gotten. And that's probably a necessity: the government is denying that there were any security forces on the streets, preferring to portray the clashes as the organic response of pro-Mubarak Egyptians to "outlaws" (as Mubarak called them) amidst the protesters. To use guns or other weapons would give the lie to that line - although it's worth noting there were some tear gas assaults.

But just because the weapons in Tahrir Square weren't sophisticated doesn't mean they were ineffective. Al Jazeera reports that an estimated 500 people have been injured in the square. It's not clear how many are dead. And there are still lots of people at the square right now.

There's a lot of bitterness amongst the protesters toward the Army right now. What looked for the last couple days like a restraint bordering on a vote of no confidence in Mubarak now looks like uniformed acquiescence to the crackdown. One protester tweets: "This is the world's tenth largest army, not a fire brigade!! Do something u animals!! There are women and children there!!"